FontAwesome isn't related to W3Schools. Here is their website: https://fontawesome.com/. It requires all of the files to work properly because the files are used for compatibility with different browsers.

Personally, I like fast and efficient websites, which is why I don't rely on third party libraries for most of my content.If I need just two icons I will create them myself, or find a site that offers free icons individually. In the web development world you have to choose between efficient or easy. Due to their generalized nature you can never expect third party libraries to be efficient.